Circadian- and light-dependent regulation of resting membrane potential and spontaneous action potential firing of drosophila circadian pacemaker neurons
Circadian- and light-dependent regulation of resting membrane potential and spontaneous action potential firing of drosophila circadian pacemaker neurons
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DOI：
10.1152/jn.00930.2007
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发表时间：
2008-02-01
影响因子：
2.5
通讯作者：
Holmes, Todd C.
中科院分区：
文献类型：
--
作者：
Sheeba, Vasu;Gu, Huaiyu;Holmes, Todd C.
果蝇脑腹侧神经元表达振荡时钟蛋白，调节昼夜节律。在新鲜解剖的果蝇全脑制备的大LNvs的全细胞电流钳记录揭示了两个自发活动模式，与两个基本模式的振荡膜电位：紧张和突发发射的钠依赖性动作电位。静息膜电位和自发性动作电位放电可通过光强度的急性变化快速可逆地调节。在cry（B）突变果蝇中，LNv电生理学光反应减弱，但未被消除，这是细胞自主光敏感蛋白CYP2P17色素的亚型。大LNv的电活动是受昼夜节律调节的，如昼夜节律主观白天相对于主观夜晚期间显著更高的静息膜电位和自发动作电位放电率和爆发放电模式的频率所示。膜电位的昼夜节律调节，自发动作电位放电频率，和模式的果蝇大LNVS密切类似哺乳动物昼夜神经元电特性，这表明在起搏神经元的生理和分子振荡器机制的一般进化保守。
The ventral lateral neurons ( LNvs) of adult Drosophila brain express oscillating clock proteins and regulate circadian behavior. Whole cell current-clamp recordings of large LNvs in freshly dissected Drosophila whole brain preparations reveal two spontaneous activity patterns that correlate with two underlying patterns of oscillating membrane potential: tonic and burst firing of sodium-dependent action potentials. Resting membrane potential and spontaneous action potential firing are rapidly and reversibly regulated by acute changes in light intensity. The LNv electrophysiological light response is attenuated, but not abolished, in cry(b) mutant flies hypomorphic for the cell-autonomous light-sensing protein CRYPTOCHROME. The electrical activity of the large LNv is circadian regulated, as shown by significantly higher resting membrane potential and frequency of spontaneous action potential firing rate and burst firing pattern during circadian subjective day relative to subjective night. The circadian regulation of membrane potential, spontaneous action potential firing frequency, and pattern of Drosophila large LNvs closely resemble mammalian circadian neuron electrical characteristics, suggesting a general evolutionary conservation of both physiological and molecular oscillator mechanisms in pacemaker neurons.